Electrical arrangements sometimes have resonance that is undesirable in that it may tend to limit efficiency and/or operational capabilities. As one example arrangement, an integrated circuit (IC) processor implemented as part of a processor package will be used to describe background resonance problems as well as example embodiments of the invention. However, practice of embodiments of the present invention is not limited thereto.
Transistors and other components may be inter-coupled on a common IC die to form, for example, a processor IC that may then be mounted on a substrate to form a package that may be subsequently mounted on a printed circuit board or motherboard for further installation in an electronic system. Designers strive to increase operating frequencies (e.g., clocking speeds) of the processor. However, as speed increases, power consumption also tends to increase. It may be difficult to provide and reliably maintain a required power level delivery to a processor IC, especially in contemporary processor systems that allow only a very low noise margin. In short, the effectiveness of the processor (e.g., operating speed) may be a function of the efficient utilization of available power.
Processor operating frequency, in most cases, is increasing at a greater rate than that of package resonant frequency. As one example, in the past decade the package resonant frequency has changed less than an order of magnitude, while processor clock rates have increased over two orders of magnitudes (e.g., 1 MHz to 2 GHz). It has been found that package resonance may disadvantageously reduce an effective available power applied to a processor's components, and consequently, may limit an attainable processor operating speed.
Capabilities of future processors needed to meet marketplace requirements are planned for operation at higher frequencies (e.g., 3, 4, 5. GHz). However the package resonance frequencies (e.g., currently of the order of approximately 50 MHz) may not experience a similar increase. With the package resonance frequencies remaining significantly low in comparison to ever increasing IC frequencies, the opportunities at which a package resonant frequency may be stimulated significantly increases. Needed are apparatus and methods to reduce resonance in IC arrangements.